两种冰草属植物光合生理特性研究  

Photosynthetic Physiological Characteristics of Two Species of Agropyron

作　　者：闫伟红[1] 徐柱[1] 马玉宝[1] 李临杭 

机构地区：[1]中国农业科学院草原研究所,农业部草地资源与生态重点开放实验室,呼和浩特010010

出　　处：《科技导报》2010年第4期42-46,共5页Science & Technology Review

基　　金：国家重点基础研究发展计划(973计划)项目(2007CB106806)

摘　　要：采用Li-6400便携式光合测定系统,测定旱作条件下引种栽培的两种冰草属植物光合生理特性。结果表明,净光合速率Pn日变化均为双峰型,第1峰值均出现在10:00左右,第2峰值均出现在16:00。在午后14:00,由于气孔限制因素所致,出现了不同程度的光合"午休"现象,PAR是引起"午休"的间接因素。蒸腾速率Tr和气孔导度Gs日变化均为双峰曲线,峰值时间与净光合速率一致。胞间CO2浓度Ci日变化近似V字形,14:00左右降至最低。两种植物叶片水压亏缺VPD变化趋势一致,而水分利用效率WUE日变化相反。上述各光合生理参数日均值大小表现为蒙古冰草高于沙生冰草。环境因子Ca和Ta对蒙古冰草的Pn日变化影响较大;Ca和RH对沙生冰草的Pn日变化影响较大,同时对两种植物的Tr日变化影响也较大;两种植物的Pn和Tr的主要生理影响因子是Gs和VPD。Abstract The photosynthetic physiological characteristics of two species of Agropyron introduced and cultivated under dry conditions were measured by Li-6400 portable photosynthesis system. The results show that the diurnal variations of net photosynthetic rates have double peaks, with the first peak at I0：00, and the second at 16：00, with ＂noon break＂ at 14：00 obviously because of constraints caused by stomata, and with PAR as an indirect factor; the diurnal variations of transpiration rate and stomata conductance also have double peak, with the same peak times as the net photosynthetic rate; the diurnal variation of intercellular CO2 concentration is roughly in a V-shape, with the minimum at 14：00; the diurnal variations of leave＇s water pressure deficit of two species are in the same trend, while the diurnal variations of water use efficiency are in the opposite trends; the averages of these photosynthetic physiological parameters of Agropyron mongolicum are higher than those of Agropyron desertorum. Ca and Ta have a greater effect on the diurnal dynamics of Pn of A. mongolicum, Ca and RH have a greater effect on the diurnal dynamics of Pn of Agropyron desertorum, while Ca and RH have a greater effect on the diurnal dynamics of Tr of two species, Gs and the VPD have a greater physiological effect on the diurnal dynamics of Pn and Tr of two species.

关 键 词：蒙古冰草 沙生冰草 净光合速率 蒸腾速率 

分 类 号：S543.9[农业科学—作物学]